1. Field of the Invention
The present invention relates to an image capturing apparatus having the function of an electronic spirit level.
2. Description of the Related Art
When deciding a camera composition in a scenery image capturing operation or the like, a spirit level is sometimes used to prevent the inclination of an image. This spirit level has a structure having an air bubble in a liquid, and is designed so that the inclination in the horizontal direction can be known based on the position of the air bubble. The spirit level is mounted on the accessory shoe of the camera when used. In addition, some recent digital cameras have an electronic spirit level function of detecting the attitude of the camera body based on an output from a three-dimensional acceleration sensor built in the camera body and displaying inclination amounts in the horizontal and vertical directions on a liquid crystal panel or viewfinder.
On the other hand, as shown in FIGS. 1A to 1D, there is commercially available an omnidirectional capturing adapter 101 which is mounted on the lens of a digital camera 102 to allow the camera to capture a panoramic image in 360° directions around the optical axis of the lens. As shown in FIG. 1D, the panoramic image captured by using the omnidirectional capturing adapter is an annular image. When, for example, capturing an image while holding the camera in the direction shown in FIG. 1B by using the omnidirectional capturing adapter, a portion 109 on the outer circumferential side corresponds to the ground direction, and a portion 110 on the inner circumferential side corresponds to the sky direction. Separately expanding this annular image by using image processing software can obtain a 360° panoramic image, as shown in FIGS. 8A and 8B.